Roof racks are popular accessories for land vehicles that provide an alternative approach to transporting large objects on the vehicle. A roof rack may comprise a pair of parallel rails that extend longitudinally along the outer panel of the roof. Alternatively, the roof rack may include more than two rails and transverse rails. Similar racks may be installed on a deck lid of a sedan or coupe style vehicle.
Depending upon the design of the roof, the outer panel of the roof may be spaced from a sub-structure mounting plate. For example, the sub-structure mounting plate may be spaced 20-60 mm away from the outer panel of the roof. A design height may be specified within the above range but substantial variation from the design height may be encountered. Fixed height fasteners may be used to secure the roof rack to the sub-structure mounting plate, but the variations due to manufacturing tolerances from the design height may adversely affect product quality.
Tightening the roof rack fastener when the distance is less than the design height may dent or deform the outer roof panel. Conversely, when the distance between the outer roof panel and the sub-structure mounting plate is greater than the design height, tightening the fastener may not result in the roof rack being fully seated to the outer panel of the roof. Poor fit or water leaks may result if the roof rack is not fully seated.
Similar problems are encountered with other parts, for example instrument panels, where an accessory or other object is attached to a surface and sub-surface structure. The primary support for the accessory is the sub-surface structure that is spaced inboard from the surface. Variations in the spacing between the surface and the sub-surface structure may create fit and finish or sealing problems.
This disclosure is directed to solving the above problems and other problems as summarized below.